There is one just down the road form Angler's.
You have to go to the National Park up-river, cross the canal and launch BELOW the weir.
BEWARE! 7 D00ds have died on that weir, DON'T shoot it! Currently it is not safe to play in but when the water is higher twill be fine to go round the side of it and mess about on the overspill.
You can paddle down to Angler's from there.